Unity Bookmarks Lens displays your bookmarks in Dash so you can easily search all your bookmarks with a click.
The new bookmarks lens only supports Firefox for now (both regular bookmarks and live bookmarks).
You can get the code for both Unity Bookmarks Lens and the packaging via Launchpad. To make it easier to install, I've uploaded it to the main WebUpd8 PPA (both the lens and the packaging have been created by Ted Gould, I've only uploaded it to the PPA) so you can install it in Ubuntu 11.10 using the following commands:
sudo add-apt-repository ppa:nilarimogard/webupd8
sudo apt-get update
sudo apt-get install bookmarks-lens
For Ubuntu 12.04, use the commands below:
sudo add-apt-repository ppa:ted/bookmarks-lens
sudo apt-get update
sudo apt-get install bookmarks-lens
Once installed, run the following command:
setsid unity
And the new Unity Bookmarks Lens should show up in Dash. If the new lens doesn't display any bookmarks, try restarting your computer.